Explain trigger, Database Management System

Assignment Help:

What is Trigger?

A trigger is a SQL procedure that initiates an action when an event (INSERT, DELETE or UPDATE) occurs. Triggers are kept in and managed by the DBMS. Triggers are used to maintain the referential integrity of data by changing the data in a systematic fashion. A trigger cannot be called or implemented; DBMS automatically fires the trigger as a result of a data modification to the associated table. Triggers can be viewed as same to stored procedures in that both having of procedural logic that is kept at the database level. Stored procedures, though, are not event-drive and are not attached to a specific table as triggers are. Stored procedures are explicitly implemented by invoking a CALL to the procedure whereas triggers are implicitly executed. In addition, triggers can also execute stored procedures.

 


Related Discussions:- Explain trigger

State the data flow diagram of functional model, State the data flow diagra...

State the data flow diagram of functional model Any action initiated by transition in the state diagram can be extended into an entire data flow diagram in functional model. Th

What are the benefits of decomposing a system, What are the benefits of dec...

What are the benefits of decomposing a system? The benefits of decomposing a system into subsystems are that after decomposition, each individual component become smaller and e

What is relational calculus, What is Relational calculus? Relational c...

What is Relational calculus? Relational calculus is a Non- Procedural language.

Information Technology, What benefits can a company gain by managing its ow...

What benefits can a company gain by managing its own information infrastructure and servicea

Erds, What are the various symbols used to draw an E-R diagram (any 3)?

What are the various symbols used to draw an E-R diagram (any 3)?

Traffic data management, This report identifies and outlines my CIS 499 pro...

This report identifies and outlines my CIS 499 project named Traffic Data Management  Systems (TDMS) .   My goal is to design a replica of all traffic issues to be implemented i

Commercial database architecture, At its most essential level the DBMS arch...

At its most essential level the DBMS architecture can be divide into two parts: the back end and the front end. The back end is responsible for managing the physical database an

What is meant by data-transfer rate, What is meant by data-transfer rate? ...

What is meant by data-transfer rate? The data-transfer rate is the rate at which data can be retrieved from or kept to the disk.

Discuss the count function, Discuss the count function? The COUNT funct...

Discuss the count function? The COUNT function used returns the number of tuples or values fixed in a query. The count function comprises two types of syntax: (1) COUNT (*)

Why do you go for sorting your query results, Why do you go for sorting you...

Why do you go for sorting your query results? SQL SELECT command to fetch data from MySQL table. Whenever you select rows, the MySQL server is free to return them in any order

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd